1. Field of the Invention
The present invention relates to a signal processing apparatus for performing signal processing including a plurality of unit signal-processing steps by means of software processing.
2. Description of the Related Art
Recently, increasingly high-performance computers have been commercially available, and moving pictures and music have been reproducible on the computers, which was difficult in the past. Particularly, there have been available video and audio signal processing applications capable of easily performing real-time signal processing by means of software processing without using traditional dedicated signal processing devices, such as digital signal processors (DSPs), or dedicated hardware.
Such signal processing applications are supported by various types of signal processing middleware, such as DirectShow which is aproduct of Microsoft® Corporation, MATLAB, which is a product of The MathWorks®, Inc., and Max/MSP, which is a product of Cycling '74.
With the use of such middleware, signal processing applications can comparatively easily implement sophisticated features. For example, audio features, such as recording and reproduction, input and output, mixing, and special effects, are implemented by means of signal processing applications. Video signal processing applications having sophisticated editing features, such as non-linear editing, have also been available.
Middleware systems with a plugin configuration are disclosed in Japanese Unexamined Patent Application Publications No. 2001-109628 and No. 7-302195. A plugin is a software application that carries out a modularized feature. This document deals with signal processing. A plugin is therefore a software application implementing a signal processing module.
A plugin allows a user to add on and use a desired signal processing module, as needed. While plugins are generally used individually, novel systems in which multiple features can be achieved by a combination of plugins have recently been developed. In the future, such multiple-plugin systems will become the mainstream of new added value systems.